• Journal of The Korean Society of Grassland and Forage Science
• /
• v.40 no.2
• /
• pp.73-79
• /
• 2020

This study was conducted to develop a technique for the stable production of Italian ryegrass(IRG) seeds in reclamation sites. Harvesting 35 days after heading in Autumn resulted in the highest production, an average of 2,232kg/ha. The production yield decreased due to seed loss as harvesting was delayed to 45 and 55 days post-heading. For the harvested 35 days post-heading, under growing rice sowing resulted in 80% seed yield of after rice sowing's; spring sowing resulted in 40%. After rice sowing using the domestic IRG seeds of 30kg/ha produced the highest seed yield of 2,507kg/ha. The highest straw yield has resulted when using the imported IRG seeds of 20kg/ha for after rice sowing 35 days post-heading fresh weight 36,667kg/ha, dry weight 14,500kg/ha, and TDN weight 7,895kg/ha.

• Journal of the Economic Geographical Society of Korea
• /
• v.12 no.4
• /
• pp.295-318
• /
• 2009

This paper explores micro-contexts of transnational migration and decision-making process of foreign migrants in Korea with four types, that is, married immigrants, immigrant workers, professional immigrants, and foreign students, analyzing dates of questionaries and interviews. Some findings can be summarized as follows. First, married immigrants and immigrant workers show relative lower level of micro-environments than professional immigrants and foreign students. Secondly, immigrants workers fill closest in geographical contiguity among immigrants' types, while married immigrants recognize more different in cultural comparison than the former. Both immigrants workers and foreign students think living environments of Korea better than other types, but immigrants workers consider relatively higher the level of technology, while foreign students evaluate lower that of education in Korea than other types. Thirdly, married immigrants give a relatively low score to the easiness of immigration, while both immigrant workers and professional immigrants give a high score to the job environment of Korea. Finally, all types of immigrants show a high portion in a self-decision making for international migration, while professional immigrants have much more experiences on visiting other countries than other types, and both married immigrants and foreign students seem to have utilized their networks with family members who live abroad.

• KEPCO Journal on Electric Power and Energy
• /
• v.2 no.1
• /
• pp.133-141
• /
• 2016

Although construction of any new nuclear power projects had not been launched since mid-1970s until recently in the USA, many new nuclear power plants have been constructed in many countries with the support of their governments mainly as part of their national energy security and electric source diversification policies. For many reasons, the nuclear power industry seemed to reclaim their renaissance from the beginning of this century and the investment in the nuclear power projects draw positive concern from the private financial sector. But the global financial crisis in 2008 and subsequent economic slow-down together with tighter bank credit regulations caused commercial banks, the main source of financing, to lose appetite for investing in new nuclear power projects. But the nuclear power economics shows that the nuclear power is viable in terms of the environmental benefit and long-term average cost compared to other power generation sources. Also doubt about nuclear power safety was much mitigated due to technology development and reinforced safety-related tests and monitoring. Therefore, the prospect for nuclear power market expansion remains positive although there are comparatively big differences among different scenarios. After Korea Electric Power Corp. won the UAE nuclear power project in December of 2009, the competition in nuclear power markets is undergoing huge changes. Competitors backed by the support of their own governments are now entering the market with many aggressive and innovative financing packages to win bids of new nuclear power projects. This report analyzed the nuclear power market prospects, competitive edges of nuclear power, risk management measures, and financing challenges and recommends alternative solutions to promote competitive edges in winning bids of new nuclear power projects.

• 대한공업교육학회지
• /
• v.39 no.1
• /
• pp.247-261
• /
• 2014

Education about invention in elementary schools has thus far be conducted mostly through special activities and talented activities rather than through normal curricula. However, with the implementation of the 2007 amended curricula, invention education was reflected as a normal subject unit in the practical subject (technology and home economics) curricula, thereby laying groundwork for invention education being able to be provided through normal subject classes. Thus, at the time when invention education has been reflected as a normal subject unit, it is meaningful to research the effects of elementary school students' experience in invention education on their invention attitudes. This study sought to research the effects of elementary school students' experience or non-experience in invention education on their invention attitudes, targeting those in regional talent private schools who did not take invention talent classes, those who received invention education, and those who did not receive invention education at all. The conclusion of this study is outlined as follows. First, students' experience in invention education proved to be positive in boosting their invention attitude, and continued invention education experience like with students in regional talent invention schools significantly boosted their invention attitudes. Second, considering that students' actual experience in invention education had positive effects on their invention attitudes, the reflection of invention education in the amended curricula was found to be very desirable in improving elementary students' attitudes about invention. Third, according to gender, male students' invention attitude level was found to be higher than that of female students, suggesting that male students more worked on computers, electronic (smart) devices and machines in daily life, leading them to further develop invention attitudes.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2005.10a
• /
• pp.153-159
• /
• 2005

Recently, various novel numerical models based on Navier-Stokes equation rave been developed for calculating wave motions in the sea with coastal or ocean structures. Among those models, Volume Of Fluid (VOF) method might be the most popular one, and it has been used for numerical simulations of wave motions including complicated phenomena of wave breakings. VOF method, however, needs enormous computation time and large computational storage memories in general, thus it is practically difficult to use VOF method for calculations in the case of random waves because long and stable computation ( e.g. for more than 100 significant wave periods) is required to obtain statistically meaningful results. On the other hand of the wave motion is potential motion, Boundary Element Method (BEM), which is a much faster and more accurate method than VOF method, am be effectively used. The aim of this study is to develop a new efficient model applicable to calculations of wave motion and/or wave-structure interactions under random waves. To achieve this, a strictly combined BEM-VOF model has been developed by making the best use of both methods' merits; VOF method is used in a restricted fluid domain around a structure where complicated phenomena of wave breakings may exist, and BEM is used in the other domains far from the disturbance where the wave motion may be assumed to be potential. The verification of the model was performed with numerical results for Stokes'5th order wave propagation and a random wave propagation.

• Environmental and Resource Economics Review
• /
• v.27 no.3
• /
• pp.495-520
• /
• 2018

Because of structural changes in the international oil market and the economy, it is widely recognized that the impact of oil shocks on the economy has weaken since the mid-1980s. This study tries to examine the validity of the recent perception about the relationship between oils shocks and the economy, estimating the time-varying effects of oil shocks on the Korean economy. The results show that the dynamic effects of oil shocks normalized to a one standard deviation has been relatively constant, in contrast to the recent perception and a number of existing studies. In addition, because the shape of impulse response functions at each point in time spanning from 1984:II to 2017:IV has not been changed significantly, it seems that the propagation mechanism of oil shocks also has not been substantially altered. These findings indicate that even though structural changes of the economy, such as the reduction in the share of oil consumption and the spread of high-efficiency energy technologies, have been rapidly progressed, it is not still enough to offset the negative effects of oil shocks. Rather, it seems that the recent perception about the shrinking effects of oil shocks is mainly due to the assumptions that do not reflect changes in the size of oil shocks. In particular, this problem appears more pronounced in the case of the typical a one standard deviation increase oil shock under homoskedasticity assumption, which is widely adopted in the most VAR analyses. Therefore, in estimating the effects of oil shocks on the economy, it is important to specify the correct model and normalization method, to reflect changes in the size of oil shocks.

• Archives of design research
• /
• no.16
• /
• pp.213-223
• /
• 1996

Illustration has been used as a means of human communication since the primitive age. And now it has become a way to express impliedly either the fragmentary or the psychological side of our life. Like it has been said in peter knock's Illustration magazine, an artist said "it was the best article ever read." Illustrator's task is to abstract and practically describe not our daily life, but every moment of the perception an object, whether it is define or indefine. It can inspire stronger perception than any other elegant language. Addition to that the practical use of illustration is increasing ever day. The target has now become various such as man, nature, art, science and so on. Therefore, at this point what illustration requires is creation, new and striking idea. It is because in order to get in to the general's living in the complicate and various society, it must show unique images and appearance. Therefore, now the illustration should induce the work which is based on synetics thoughts, not simple improving skill. Now we must restrain futional and diagrammatic illustration education and be able to thik of free and abundant characteristics. It will eventually help students to feel the value of human life and free themselves from the reality of present education which is getting machinized and instrumentalized.entalized.

• The KIPS Transactions:PartC
• /
• v.13C no.4 s.107
• /
• pp.471-480
• /
• 2006

Recently, multimedia communication services, such as video conferencing and voice over IP, have been rapidly spread. H.323 is an international standard that specifies the components, protocols and procedures that provide multimedia communication services of real-time audio, video, and data communications over packet networks, including IP based networks. H.323 is applied to many commercial services because it supports various network environments and has a good performance. But communication services based on H.323 may have some problem because of current network trouble or mis-implementation of H.323. The understanding of this problem is a critical issue because it improves the quality of service and is easy to service maintenance. In this paper, we implement the analysis system for H.323 protocol wihch includes H.245, H.225.0, RTP, RTCP, and so on. Tills system is able to capture, parse, and present the H.323 protocol in real-time. Through the operation test and performance evaluation, we prove that our system is a useful to analyze and understand the problems for communication services based on H.323.

• KIPS Transactions on Software and Data Engineering
• /
• v.7 no.1
• /
• pp.9-18
• /
• 2018

Recently, the use of image stitching technology has been increasing as the number of contents based on virtual reality increases. Image Stitching is a method for matching multiple images to produce a high resolution image and a wide field of view image. The image stitching is used in various fields beyond the limitation of images generated from one camera. Image Stitching detects feature points and corresponding points to match multiple images, and calculates the homography among images using the RANSAC algorithm. Generally, corresponding points are needed for calculating conversion relation. However, the corresponding points include various types of noise that can be caused by false assumptions or errors about the conversion relationship. This noise is an obstacle to accurately predict the conversion relation. Therefore, RANSAC algorithm is used to construct an accurate conversion relationship from the outliers that interfere with the prediction of the model parameters because matching methods can usually occur incorrect correspondence points. In this paper, we propose an algorithm that extracts more accurate inliers and computes accurate transformation relations by using correspondence point relation information used in RANSAC algorithm. The correspondence point relation information uses distance ratio between corresponding points used in image matching. This paper aims to reduce the processing time while maintaining the same performance as RANSAC.

• Resources Recycling
• /
• v.25 no.1
• /
• pp.48-59
• /
• 2016

The earth has been warming due to $CO_2$ gas emissions from fossil fuel cars and a ship. So the hydrogen fuel cell vehicle(FCV) using hydrogen as a fossil fuel alternative energy is in the spotlight. Hyundai Motor Company of Korea and a car companies of the US, Japan, Germany is developing a FCV a competitive. Obtained hydrogen as a by-product of the coke plant, oil refineries, chemical plants of steel mill, coal is reacted with steam at high temperatures, methane gas, manufacture of high purity hydrogen Methane Steam Reforming and hydrogen detachable reforming method using the Pressure Swing Adsorption or Membrane Reforming technical or decomposition of water to produce electricity. Hydrogen is the electronic industry, metal and chemical industries, which are used as rocket fuel, etc. are used in factories, hospitals, home of the fuel Ene.Farm system or FCV. And a method of storing hydrogen is to store liquid hydrogen and a method for compressing normal hydrogen to the hydrogen container, by storing the latest hydride or Organic chemical hydride method is used to carry the hydrogen station. Korea is currently 13 hydrogen stations in place and in operation, plans to install a further 43 places.